1 /*
2  * Copyright (C) 2010 Google Inc. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are
6  * met:
7  *
8  *     * Redistributions of source code must retain the above copyright
9  * notice, this list of conditions and the following disclaimer.
10  *     * Redistributions in binary form must reproduce the above
11  * copyright notice, this list of conditions and the following disclaimer
12  * in the documentation and/or other materials provided with the
13  * distribution.
14  *     * Neither the name of Google Inc. nor the names of its
15  * contributors may be used to endorse or promote products derived from
16  * this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #ifndef ScopedEventQueue_h
32 #define ScopedEventQueue_h
33 
34 #include <wtf/Noncopyable.h>
35 #include <wtf/PassOwnPtr.h>
36 #include <wtf/PassRefPtr.h>
37 #include <wtf/Vector.h>
38 
39 namespace WebCore {
40 
41 class Event;
42 
43 class ScopedEventQueue {
44     WTF_MAKE_NONCOPYABLE(ScopedEventQueue);
45 
46 public:
47     ~ScopedEventQueue();
48 
49     void enqueueEvent(PassRefPtr<Event>);
50     void dispatchAllEvents();
51     static ScopedEventQueue* instance();
52 
53     void incrementScopingLevel();
54     void decrementScopingLevel();
55 
56 private:
57     ScopedEventQueue();
58     static void initialize();
59     void dispatchEvent(PassRefPtr<Event>) const;
60 
61     Vector<RefPtr<Event> > m_queuedEvents;
62     unsigned m_scopingLevel;
63 
64     static ScopedEventQueue* s_instance;
65 };
66 
67 class EventQueueScope {
68     WTF_MAKE_NONCOPYABLE(EventQueueScope);
69 
70 public:
EventQueueScope()71     EventQueueScope() { ScopedEventQueue::instance()->incrementScopingLevel(); }
~EventQueueScope()72     ~EventQueueScope() { ScopedEventQueue::instance()->decrementScopingLevel(); }
73 };
74 
75 }
76 
77 #endif // ScopedEventQueue_h
78